The Court’s opening:
 A dark backyard. A trespasser. A police search. A gun. Some ammunition. Drugs. Cellphones. Cash. Several charges. And convictions.
 The appellant, Peterkin, says the police had no authority to search him early that August morning. The things they found on his person should not have been admitted in evidence at his trial. He should not have been convicted. He wants another trial.
 As I will explain, Peterkin’s convictions rest on solid ground. The police search was lawful. The evidence it yielded, admissible. I would dismiss his appeal.
The Court discusses some governing principles around police searches:
 The principles that define the basis upon and scope within which police may conduct a safety search incidental to an investigative detention control our decision on this ground of appeal.
 In R. v. Waterfield, 1985 CanLII 41 (SCC),  1 Q.B. 164, the English Court of Criminal Appeal articulated the test for whether a police officer has acted within his or her common law powers. Under the Waterfield analysis, to determine whether an officer’s prima facie unlawful interference with an individual’s liberty or property falls within his or her common law powers, a court must engage in two steps of analysis:
- Does the police conduct in question fall within the general scope of any duty imposed on the officer by statute or common law?
- If so, in the circumstances of this case, did the execution of the police conduct in question involve a justifiable use of the powers associated with the engaged statutory or common law duty?
See Waterfield, at pp. 170-171; R. v. Mann, 2004 SCC 52 (CanLII),  3 S.C.R. 59, at paras. 24-26.
The Court also discusses Investigative Detention:
 The Waterfield analysis has been applied to bestow on police officers a limited power to detain a person for investigative purposes: Mann, at paras. 23-24, 34.
 The test for determining whether an investigative detention is justifiable under the second prong of Waterfield is one of reasonable suspicion. An investigative detention must be viewed as reasonably necessary on an objective view of all the circumstances informing the officer’s suspicion that there is a clear nexus between the prospective detainee and a recent or ongoing criminal offence: Mann, at para. 34. To conduct this analysis, we must assess the overall reasonableness of the detention decision, testing it against all the circumstances, most notably:
- the extent to which the interference with individual liberty is necessary to perform the officer’s duty;
- the liberty that is the subject of the interference; and
iii. the nature and extent of the interference.
See Mann, at para. 34.
 To be justifiable, the investigative detention must also be executed in a reasonable manner. The investigative detention should be brief and does not impose an obligation on the detained individual to answer questions posed by the police: Mann, at para. 45.
The Court ultimately dismisses the appeal.